The martyrdom starts with the story about the niece of the emperor Domitian, Domitilla. Her eunuchs, Nereus and Achilles, were converted to Christianity by the Apostle Peter. They persuade Domitilla to convert too and to embrace holy virginity. They are sent to exile by the emperor Domitian. Also two disciples of Simon the Magus are exiled there and they claim publicly that their master was innocent in his dispute with Peter. Nereus and Achilles convince the crowd to write a letter to Marcellus, the son of the prefect Marcus, to learn the truth about Peter and Simon. The martyrdom quotes then the reply of Marcellus. The letter concerns the case of Simon the Magus but also gives account of a certain Petronilla. She was paralysed and Peter did not heal her so that she could gain perfectness by herself and be healed by her own prayers.
15. [...] Et quoniam nimis speciosa erat, venit ad eam Flaccus Comes cum militibus, ut eam sibi uxorem assumeret. Cui Petronilla ait: Ad puellam inermem cum militibus armatis venisti: si uxorem me habere vis, fac matronas et virgines honestas ad me post tres dies venire, ut cum ipsis veniam ad domum tuam. Factum est autem ut trium dierum acceptum spatium Virgo sanctis jejuniis et orationibus occuparetur, habens secum sanctam Virginem Feliculam collactaneam suam, in Dei timore perfectam. Tertio itaque die veniens ad eam s. Nicomedes presbyter, celebravit mysteria Christi. Virgo autem sacratissima, mox ut Christi sacramentum accepit, reclinans se in lectum, emisit spiritum. Factumque est, ut omnis turba matronarum et virginum, quae fuerant a Flacco adductae, exequias funeris sanctae Virginis celebrarent.
Then the martyrdom of Felicula is related.
17. Sanctus autem Nicomedes Presbyter in speculis positus occulte levavit corpus, et pernoctanter in biroto perduxit ad casselam suam, septimo milliario ab Urbe Roma via Ardeatina, et ibi eam sepelivit: in quo loco fructificant orationes ejus usque in hodiernum diem. Pervenit autem ad Flaccum hoc fecisse Nicomedem Presbyterum, et fecit eum teneri et duci ad sacrificandum. Qui cum diceret: Ego non sacrifico, nisi Deo omnipotenti qui regnat in coelis, non his diis qui in templis quasi in carceribus clausi custodiuntur. Cum haec et multa talia diceret, plumbatis diutissime caesus migravit ad Dominum. Corpus vero ejus in Tiberim praecipitatum est. Clericus vero ejusdem Presbyteri, nomine et opere Justus, collegit corpus ejus, et posuit in biroto suo, et duxit ad horticellum suum juxta muros via Nomentana, et illic sepelivit illud: in quo orantes Dominum, consequuntur quae postulant interventu Martyris ejus, qui passus est pro nomine Domini nostri Jesu Christi. [...]
(Acta Sanctorum Maii, vol. 3, 10-11)