The show regular - played by Steve McFadden - will collapse at Walford nightclub R&R in the New Year as his health takes a sudden turn for the worse.
According to The Mirror, a further twist will see Phil taunted and "left for dead" by his long-time nemesis Ian Beale (Adam Woodyatt), who witnesses his shock medical scare.
The surprise turn of events comes after Phil discovers Ian's affair with Albert Square temptress Glenda (Glynis Barber) and demands cash in return for his silence - while continuing his own secret relationship with the blonde.
A source said: "Ian follows Phil into R&R to give him the [blackmail] money but he walks in on Phil and Glenda getting it on. The passion is too much for Phil and he collapses.
"Phil is gasping for air and Glenda is yelling for help. Ian tells her to go and call an ambulance while he waits. He then promises to tell Phil's girlfriend Shirley about his affair and take his son Ben to live with him if Phil doesn't make it. Ian then leaves him for dead."
Phil's new storyline is expected to air in January.
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