Although happily married, Jo still appreciates a fine specimen of a man when she sees one - and CBB's Calum appears to be floating her boat.
Last night, Jo, who played Tanya Branning in EastEnders for seven years, took to Twitter and confessed: "Ok. That's it. I'm saying it. He's just beautiful. I've slightly fallen for @CalumBest I really hope he doesn't go out before the nasty one!"
We presume by "the nasty one" that Jo is referring to Perez Hilton? The US blogger faces the chop alongside Calum, Alicia Douvall and Nadia Sawalha in tonight's live show and has caused mayhem since arriving in the house.
Jo had better get in line though, as she's not the only one to lust after Calum. Earlier this week, TOWIE's Gemma Collins went as far as to say she is "in love" with Calum. Oo-err!
Meanwhile, it's been a busy time for Jo recently. The actress, who left EastEnders in 2013, has just wrapped her latest project. Later this year, Jo will star alongside Michelle Keegan in new BBC One show Ordinary Lives.
And if that's not enough, EastEnders fans have been rejoycing after Jo confirmed she will be returning to Albert Square as Tanya Branning next month to take part in the soap's 30th Anniversary celebrations.